Impregnated-wood brake lining and process for making same



' is preferably a hard and Patented May 11, 1926.

WILLIAM EICHHOIiZ, OF CICERO, ILLINOIS.

IMPBEGNATED-INOOD BRAKE LINING AND PROCESS FOR MAKING SAME.

No Drawing.

The present invention relates to impregnating wood to be used as a lining in. door checks, and has particular reference to impregnating the wood to be used as a brake lining in door checks of the kind referred to in U. S. Patent No. 1,266,864, May 1, 1918.

For the successful operation of door checks of the kind referred to, it is necessary that the brake lining used therein should be self-lubricating to the necessary extent, but it should be borne in mind that the amount of lubrication, while being suliicient, must not be excessive. The lubrication also should be continuous, that is to say the wood pieces should be self-lubricating to the desired extent, which condition should last during the entire life of the brake lining. Such a condition, as will be obvious, is diflicult to secure, but after much experimentation I have found that the same can be successfully accomplished in accordance with the simple process of the present invention. The invention has for its object, according- 1y, to produce a brake lining material suitable for door checks of the kind referred to, which shall be thoroughly impregnated with the lubricant material, and which at the same time will be free from excessive lubrication and will be capable of lasting for a very long time.

In accordance with the present invention, the material for making the brake lining relatively tough wood, which material I have found can be successfully impregnated with tallow such as mutton tallow or beef tallow, this material preferably being used alone, that is to say without liquid oil, and without the use of volatile solvents.

The pieces of hard wood, after being cutinto the size and shape required, are immersed in a bath of molten tallow, at a temperature of about 150 F. The wood should be immersed and should be kept immersed in the solution for a substantial. time, for example one-half hour.

Application filed August 17, 1825. Serial No. 50,830.

During this operation it is preferable to keep the temperature at about 150 F., during the entire time of immersion, although it will be understood that the temperature can vary more or less, and obviously the immersion of a considerable number of pieces of the hard wood into the bath of molten tallow will lower its temperature somewhat.

The wood is then removed from the bath, and is placed in an oven, in which it is heated to a temperature of about 200 F., and is maintained at this temperature for say one-half hour. It is then removed from the oven, and all excess of the tallow which remains on the outside of the piece of wood is removed, being wiped off in any suitable inlanner, as by a piece of cotton waste or the The wood will then be found to be uniformly impregnated with the tallow, and in this condition is ready to be placed into the door check, as a brake lining.

Nood treated in the manner above described is found to give just the proper degree of lubrication, and is found to wear for a very long time, whether the door check is used frequently or only a very little.

1. A. process which comprises immersing hard wood in the form of door check brake linings, in a bath of molten tallow, substan tially free from added normally liquid oils, and allowing the same to soak therein while said molten tallow is at about 150 F, then removing from the bath and baking at about 200 F, then wiping off the excess of the fatty matter.

2. A hard wood brake lining for door checks, impregnated with tallow, and free from excess thereof.

3. A method of treating door check lin- I ings composed of hard wood, which comprises impregnating the same with molten tallow and removing the excess of the latter. In testimony whereof I ai'lix my signature.

WILLIAM EIGHHOLZ. 

